Abstract: A seal apparatus is disclosed for sealing an outlet of a pressurized chamber from fluid loss from the chamber and contamination to the chamber. The apparatus includes certain combinations of (a) a chamber outlet structure; (b) a removable cover; (c) means for reversibly connecting the cover to the chamber outlet structure; and (d) a compressible self-energizing ring having a surface which consists essentially of a material selected from the group consisting of noble metals, noble metal alloys and polytetrafluoroethylene, which has a hardness selected to substantially avoid deformation when the cover is sealed to the chamber outlet structure.Also disclosed are certain pressure vessels for hydrothermal crystal growth using a crystal growth media, which comprise (a) a vessel base and (b) a removable vessel cover.

Abstract: A europium-doped barium fluorohalide photostimulable phosphor comprises an amount of oxygen sufficient to create a concentration of anion vacancies effective to substantially increase the stored photostimulable energy, compared to a non-oxygen-treated phosphor.

Abstract: A process for producing BaFBr:Eu phosphors in which a slurry of an Eu halide, BaFBr and BaBr.sub.2 is spray dried to produce spherical agglomerates which are then fired and cooled by an inert atmosphere, washed to remove unreacted BaBr.sub.2 and dried to produce a powder.

Abstract: A process for producing BaFBr:Eu phosphors in which a slurry of an Eu halide, BaFBr and BaBr.sub.2 is spray dried to produce spherical agglomerates which are then fired and cooled by an inert atmosphere, washed to remove unreacted BaBr.sub.2 and dried to produce a powder.

Abstract: There is disclosed an optical waveguide comprising a K.sub.1-x Rb.sub.x TiOmO.sub.4 single crystal substrate, wherein x is from 0 to 1 and M is P or As, having at least one optically smooth surface wherein sufficient K.sup.+ and/or Rb.sup.+ have been replaced by ions selected from at least one of H.sup.+ and NH.sub.4.sup.+ and, optionally, at least one monovalent ion selected from Rb.sup.+, Cs.sup.+, Tl.sup.+, and/or at least one divalent ion selected from Ba.sup.+2, Sr.sup.+2, Ca.sup.+2 and Pb.sup.+2 to chance the surface index of refraction at least a 0.00025 with respect to the index of refraction of the single crystal substrate. One process disclosed for producing an optical waveguide comprises the steps of contacting at least one optically smooth surface of a single crystal of K.sub.1-x Rb.sub.x TiOmO.sub.4 with an ion exchange medium capable of supplying said replacement ions, at a temperature of from about 100.degree. C. to about 600.degree. C.

Abstract: A europium-doped barium fluorohalide photostimulable phosphor comprises an amount of oxygen sufficient to create a concentration of anion vacancies effective to substantially increase the stored photostimulable energy, compared to a non-oxygen-treated phosphor.

Abstract: There is disclosed an optical waveguide comprising a K.sub.1-x Rb.sub.x TiOMO.sub.4 single crystal substrate, wherein x is from 0 to 1 and M is P or As, having at least one optically smooth surface wherein sufficient K.sup.+ and/or Rb.sup.+ have been replaced by ions selected from at least one of H.sup.+ and NH.sub.4.sup.+ and, optionally, at least one monovalent ion selected from Rb.sup.+, Cs.sup.+, Tl.sup.+, and/or at least one divalent ion selected from Ba.sup.+2, Sr.sup.+2, Ca.sup.+2 and Pb.sup.+2 change the surface index of refraction at least about 0.00025 with respect to the index of refraction of the single crystal substrate. One process disclosed for producing an optical waveguide comprises the steps of contacting at least one optically smooth surface of a single crystal of K.sub.1-x Rb.sub.x TiOMO.sub.4 with an ion exchange medium capable of supplying said replacement ions for sufficient time at a temperature of from about 100.degree. C. to about 600.degree. C., and cooling the resulting crystal.

Abstract: The activity of nonfused methanol dissociation catalysts containing copper and optionally chromium, magnesium, calcium, barium, strontium, manganese, molybdenum, ruthenium and palladium can be improved by the incorporation of 0.1 to 20 weight percent amorphous silica.

Abstract: A composition is disclosed which consists essentially of doped crystalline MTiOXO.sub.4 (wherein M is selected from the group consisting of K, Rb and Tl, X is selected from the group consisting of P and As) which contain at least about 100 ppm total of at least one dopant selected from the group consisting of Ga, Al and Si. The compositions generally have low ionic conductivity, and may be prepared using an improved flux process wherein Ga, Al and/or Si dopant is added to the flux in a total amount of at least about 0.5 mole % and the crystallization temperature is controlled to provide a crystalline composition containing the desired amount of dopant.

Abstract: A hydrothermal process for growing a crystal of MTiOXO.sub.4 at an elevated temperature is disclosed which employs a growth medium comprising a mineralizer solution, and is characterized as employing aqeuous mineralizer solution in which the concentration of M is at least about 8 molar, and as employing a growth region temperature of less than about 500.degree. C. and/or a pressure of less than 14,000 psi during crystallization. M is selected from the group consisting of K, Rb, Tl and NH.sub.4 and mixtures thereof, and X is selected from the group consisting of P and As and mixtures thereof.

Abstract: There is disclosed a process for producing an optical waveguide comprising contacting at least one optically smooth surface of a single crystal of K.sub.1-x Rb.sub.x TiOMO.sub.4 wherein x is from 0 to 1 and M is P or As with a specified molten salt of at least one of Rb, Cs and Tl at a temperature of from about 200.degree. C. to about 600.degree. C. for a time sufficient to increase the surface index of refraction at least about 0.00025 with respect to the index of refraction of the starting crystal, and cooling the resulting crystal. The product made thereby and a waveguide device using the same are also disclosed.

Abstract: There is disclosed a process for producing an optical waveguide comprising contacting at least one optically smooth surface of a single crystal of K.sub.1-x Rb.sub.x TiOMO.sub.4 wherein x is from 0 to 1 and M is P or As with a specified molten salt of at least one of Rb, Cs and Tl at a temperature of from about 200.degree. C. to about 600.degree. C. for a time sufficient to increase the surface index of refraction at least about 0.00025 with respect to the index of refraction of the starting crystal, and cooling the resulting crystal. The product made thereby and a waveguide device using the same are also disclosed.

Abstract: Process for preparing spheroidal particulate BaFCl:Eu phosphor having a narrow size distribution, which process comprises:(a) spray drying the slurry comprised of BaFCl, or the precursors thereof, a europium halide, and a BaCl.sub.2 flux in a liquid under conditions which produce porous spheroidal agglomerates of BaFCl, or the precursors thereof, BaCl.sub.2, and the europium halide, the agglomerates having an average diameter larger than the desired diameter of the particulate phosphor;(b) firing the porous spheroidal agglomerates of step (a) in a flowing inert atmosphere for about 10 to about 120 minutes at a temperature of about 650.degree. C. to about 950.degree. C.;(c) cooling the fired material of step (b) to ambient temperature in an inert atmosphere;(d) washing the cooled material of step (c) with water to remove BaCl.sub.2 ; and(e) drying the washed material of step (d) to remove the water and to produce the free flowing powder comprised of spheroidal particulate BaFCl:Eu phosphor.

Abstract: Method for making a pyrochlore of the formula Bi.sub.2-x M.sub.x B.sub.2 O.sub.7-z by firing finely divided particles of bismuth oxycarbonate. The pyrochlores made by the invention have a high surface area and are especially useful as the conductive phase for thick film resistors.

Abstract: A process for preparing BaFCl:Eu phosphors of controllable particle size and size distribution is provided. The process comprises (a) preparing an intimate mixture of fine particles of BaFCl, a europium source, preferably water-soluble EuCl.sub.3, and a water-soluble chloride as flux; (b) firing the mixture in an inert atmosphere at a temperature in the range of about 550.degree.-900.degree. C and above the liquid temperature of the flux for a time sufficient to effect reaction and diffusion, and (c) washing the fired product with water to remove the chloride flux. By preselecting the combination of firing temperature and flux concentration in the mixture, phosphor particles of a predetermined size and size distribution can be obtained. This control of the phosphor product is especially advantageous when the intimate mixture is formed in an aqueous medium.

Abstract: Phosphors of the formula Ba.sub.1-x-y-z Sr.sub.x Eu.sub.y R.sub.z FCl when R is one or more of Sm, Dy, Sb, Bi or Zn, x is from 0 to 0.1, y is from 0.0001 to 0.2 and z is from 0 to 0.1 having high efficiency and low lag are made by (1) intimately mixing a substantially stoichiometric mixture of the appropriate metal halides having at least 30% of particles less than 1.5.mu. with the remaining particles having an average particle size less than 3.mu. (2) firing in an atmosphere free of hydrogen at 600.degree. to 950.degree. C for a time sufficient to effect reaction and (3) pulverizing the sintered product.